United States Antimony Corporation and its subsidiaries in the U.S. and Mexico (USAC) sell processed antimony, zeolite, and precious metals products in the U.S. and Canada.
The company processes antimony ore primarily into antimony oxide, antimony metal, and antimony trisulfide. Its antimony oxide is used to form a flame-retardant system for plastics, rubber, fiberglass, textile goods, paints, coatings and paper, as a color fastener in paint, and as a phosphorescent agent in fluorescent light b...
United States Antimony Corporation and its subsidiaries in the U.S. and Mexico (USAC) sell processed antimony, zeolite, and precious metals products in the U.S. and Canada.
The company processes antimony ore primarily into antimony oxide, antimony metal, and antimony trisulfide. Its antimony oxide is used to form a flame-retardant system for plastics, rubber, fiberglass, textile goods, paints, coatings and paper, as a color fastener in paint, and as a phosphorescent agent in fluorescent light bulbs. The company’s antimony metal is used in bearings, storage batteries, and ordnance. The company’s antimony trisulfide is used as a primer in ammunition. In its operations in Idaho, the company mines and processes zeolite, a group of industrial minerals used in soil amendment and fertilizer, water filtration, sewage treatment, nuclear waste and other environmental cleanup, odor control, gas separation, animal nutrition, and other miscellaneous applications. The company recovers precious metals, primarily gold and silver, at its plant in Montana from antimony concentrates.
Recent Developments
The company has two subsidiaries in Mexico, U.S. Antimony de Mexico, S.A. de C.V. (‘USAMSA’) and Antimonio de Mexico, S.A. de C.V. (‘ADM’). On March 11, 2024, the company shuts down the operations of USAMSA, terminated a majority of USAMSA employees, and announced its plans to sell, lease, or dispose of its USAMSA subsidiary, operations, or assets. The USAMSA subsidiary primarily includes the company’s Madero antimony and precious metals plant in Parras de la Fuente Coahuila, Mexico and its Puerto Blanco antimony and precious metals plant in San Luis de la Paz Guanajuato, Mexico. The company intends to sell or lease its USAMSA subsidiary, operations, or assets over the next year and has initiated an active search for buyers or leasing opportunities of its operations and/or existing assets. The company will maintain its existing Los Juarez mining claims and concessions in Cadereyta de Montes Queretaro, Mexico, which are included in the company’s ADM subsidiary. There are presently no active operations at Los Juarez.
Products, Markets, and Segments
The company’s products primarily consist of the following:
Antimony: Includes antimony oxide, antimony metal, and antimony trisulfide;
Zeolite: Includes coarse and fine zeolite crushed in various sizes; and
Precious Metals: Includes unrefined and refined gold and silver.
All sales of antimony, zeolite, and precious metals products are to customers in the United States and Canada.
The company is organized and managed by the following four segments, which represent the company’s operating units: United States Antimony segment, Mexico Antimony segment, Zeolite segment, and Precious Metals segment.
United States Antimony Segment
The company’s United States Antimony segment consists of an antimony plant in the Burns Mining District of Sanders County in Montana, which primarily produces antimony oxide, antimony metal, antimony trisulfide, and precious metals. Antimony oxide is a fine, white powder. The company’s antimony oxide is used in conjunction with a halogen to form a synergistic flame-retardant system for plastics, rubber, fiberglass, textile goods, paints, coatings, and paper. The company’s antimony oxide is also used as a color fastener in paint and as a phosphorescent agent in fluorescent light bulbs. The company’s antimony metal is used in bearings, storage batteries and ordnance. The company’s antimony trisulfide is used as a primer in ammunition. The precious metals processed at this plant in montana are included in the company’s precious metals segment.
The company closed its antimony mine and mill in Montana in December 1983 because antimony ore could be purchased more economically from foreign sources. The company’s mine and mill are approximately 1 mile from the company’s current antimony smelter plant in Montana. The company holds one patented claim at the mine. The environmental permitting process precludes mining at the company’s mine in Montana.
As a result of the mine and mill closure, the company has relied on sources outside the U.S. for antimony ore since 1983, and there are risks of interruption in procurement from these sources and volatile changes in world market prices for these materials that are not controllable by the company. The company anticipates continuing to receive antimony ore primarily from a supplier in Canada but will continue to explore Mexico and Central America for suppliers of antimony ore, assuming economics are profitable. The acquisition of antimony ore is technically complex and a function of the country’s laws and regulations. the company’s purchasing consequently requires flexibility regarding supply agreements and is tailored accordingly to specific suppliers.
Mexico Antimony Segment
The company has two subsidiaries in Mexico, USAMSA and ADM. The company shuts down the operational activities of USAMSA on March 11, 2024, which primarily includes the following two antimony and precious metals processing plants in Mexico: (1) the Madero smelter in Coahuila, and (2) the Puerto Blanco flotation mill, oxide circuit, and cyanide leach circuit in Guanajuato. The company’s Madero smelter processes antimony ore primarily into antimony metal and an intermediate stage of antimony. The company’s Puerto Blanco plant includes crushing equipment, a flotation mill, and an oxide circuit to process and produce an intermediate stage of antimony and a cyanide leach circuit and settling pond that recovers precious metals after the ore goes through the crushing and flotation cycles. The intermediate stage of antimony produced at Madero and Puerto Blanco is shipped to the company’s plant in Montana for further processing to produce antimony oxide and metal. The precious metals processed at Madero and Puerto Blanco, which were shut down as well, are included in the company’s Precious Metals Segment. The company intends to sell or lease its USAMSA subsidiary, operations, or assets over the next year and has initiated an active search for buyers or leasing opportunities of its operations and/or existing assets.
The company will maintain its existing Los Juarez mining claims and concessions in Cadereyta de Montes Queretaro, Mexico, which are included in the company’s ADM subsidiary. There are presently no active operations at Los Juarez.
Zeolite Segment
The company’s Zeolite segment consists of a mine and mill in Preston, Idaho, Bear River Zeolite, Inc. (‘BRZ’), which produces zeolite. The company’s zeolite is used for various purposes including soil amendment and fertilizer, water filtration, sewage treatment, nuclear waste and other environmental cleanup, odor control, gas separation, animal nutrition, and other miscellaneous applications.
Bear River Zeolite, Inc. (BRZ) has a lease with Zeolite, LLC that entitles BRZ to surface mine and process zeolite on property in Preston, Idaho. This Zeolite LLC lease also requires BRZ to pay to the lessor on March 1 of each year during the term of the lease, which ends March 1, 2025. BRZ also pays two other royalties on the sale of zeolite products. On a combined basis, BRZ pays royalties ranging from 8% to 13% on the sale of zeolite products. In addition, BRZ can surface mine and process zeolite on property owned by the U.S. Bureau of Land Management that is adjacent to the company’s Preston, Idaho property after obtaining required permits.
‘Zeolite’ refers to a group of industrial minerals that consist of hydrated aluminosilicates that hold cations such as calcium, sodium, ammonium, various heavy metals, and potassium in their crystal lattice. Water is loosely held in cavities in the lattice. BRZ zeolite is regarded as one of the best zeolites in the world due to its high cation exchange capacity (CEC) of approximately 180-220 meq/100 gr. (which predicts plant nutrient availability and retention in soil), its hardness and high clinoptilolite content (which is an effective barrier to prevent problematic radionuclide movement), its absence of clay minerals, and its low sodium content.
The company’s zeolite is used in:
Soil Amendment and Fertilizer: Zeolite has been successfully used to fertilize golf courses, sports fields, parks and common areas, and high value agricultural crops.
Water Filtration: Zeolite is used for particulate, heavy metal and ammonium removal in swimming pools, municipal water systems, fisheries, fish farms, and aquariums.
Sewage Treatment: Zeolite is used in sewage treatment plants to remove nitrogen and as a carrier for microorganisms.
Nuclear Waste and Other Environmental Cleanup: Zeolite has shown a strong ability to selectively remove strontium, cesium, radium, uranium, and various other radioactive isotopes from solutions. Zeolite can also be used for the cleanup of soluble metals such as mercury, chromium, copper, lead, zinc, arsenic, molybdenum, nickel, cobalt, antimony, calcium, silver and uranium.
Odor Control: A major cause of odor around cattle, hog, and poultry feed lots is the generation of the ammonium in urea and manure. The ability of zeolite to absorb ammonium prevents the formation of ammonia gas, which disperses the odor.
Gas Separation: Zeolite has been used for some time to separate gases, to re-oxygenate downstream water from sewage plants, smelters, pulp and paper plants, and fishponds and tanks, and to remove carbon dioxide, sulfur dioxide and hydrogen sulfide from methane generators as organic waste, sanitary landfills, municipal sewage systems, animal waste treatment facilities, and is excellent in pressure swing apparatuses.
Animal Nutrition: According to certain third-party research, feeding up to 2% zeolite increases growth rates, decreases conversion rates, and prevents scours. Many cattle are being fed zeolite in feed lots located in the United States.
Miscellaneous Uses: Other uses include catalysts, petroleum refining, concrete, solar energy and heat exchange, desiccants, pellet binding, horse and kitty litter, floor cleaner, traction control, ammonia removal from mining waste, and carriers for insecticides, pesticides and herbicides.
Precious Metals Segment
The company’s Precious Metals segment consists of three precious metals recovery plants, one that is operated in conjunction with the antimony processing plant in Montana and two that were shut down on March 11, 2024, that were operated in conjunction with the antimony processing plants at the company’s Madero and Puerto Blanco operations in Mexico. Precious metals are recovered in the leach circuit and settling pond after the ore goes through the crushing and flotation cycles. When precious metals are contained in antimony source, the metallurgical techniques employed for the recovery of antimony are altered to also recover the precious metals. In 2023, the principal source of antimony concentrates bearing precious metals came from the company’s Canadian supplier, who also purchases precious metals from the company.
Concentration of Sales
During the year ended December 31, 2023, the company sold 10% or more of its product which generated a revenue of 46% in 2023.
Regulatory Matters
The company is subject to the requirements of the Federal Mining Safety and Health Act of 1977, the Occupational Safety and Health Administration’s regulations, the states of Montana and Idaho, federal and state health and safety statutes and Sanders County, Montana and Franklin County, Idaho health ordinances.
The company is subject to the regulations of the Mine Safety and Health Administration (‘MSHA’) in the United States and the Mexico Ministry of Economy and Mining in Mexico, and work with these agencies to address issues outlined in any investigations and inspections and continue to evaluate the company’s safety practices.
The company is under the regulatory jurisdiction of the U.S. Forest Service and subject to the operating permit requirements of the Montana Department of Environmental Quality. Some reclamation activities have been performed under the supervision of the U.S. Forest Service and Montana Department of Environmental Quality.
The company has retirement and reclamation obligations in Mexico that are under The Secretary of Environment and Natural Resources (‘SEMARNAT’) and The Federal Attorney for Environmental Protection (‘PROFEPA’) based on the Program for Environmental Vigilance (‘PVA’).
History
United States Antimony Corporation was founded in 1968. The company was incorporated in Montana in 1970.